Validation study of a Spanish version of the modified Telephone Interview for Cognitive Status (STICS-m)

To compare the Spanish version of the modified Telephone Interview of Cognitive Status (STICS-m) with the Mini-Mental State Examination (MMSE) and predict its ability to detect the development of dementia.

106 participants in a dietary intervention trial underwent face-to-face evaluation with the MMSE, and phone interview with the STICS-m. The correlation between STICS-m and MMSE was assessed with the intraclass correlation coefficient (ICC) of consistency. Secondly, 932 participants over 55 years old from the "Seguimiento Universidad de Navarra" cohort were evaluated with the STICS-m and data on dementia diagnosis were gathered (median follow-up time of 6.5 years). A logistic regression model evaluated the association between STICS-m score or 2-year changes in STICS-m score and risk of developing dementia, adjusting for ApoE, age and years of university education.

The ICC between the MMSE and the STICS-m was 0.31 (95% confidence interval [95%CI]: 0.13-0.48). The adjusted odds ratio (OR) for the development of dementia for each additional point in the baseline STICS-m score was 0.85 (95%CI: 0.72-1.02; p=0.084). When considering the 2-year change in the STICS-m score as exposure, the OR for the development of dementia was 0.79 (95%CI: 0.67-0.93; p=0.006).

The weak correlation between the STICS-m and the MMSE reflects moderate-low concurrent validity. Even so, the STICS-m can be regarded as an useful tool in the epidemiological setting since increasing scores appear to be able to predict a lower risk of developing dementia.